The destruction of plant seedlings can occur by the attack by insects or other pests that live in the soil, such as the commonly known cutworm. Typically, such pests attack the plants when they are seedlings and first planted before they have the ability to grow sufficiently to be more resistant to such attacks. These pests will eat at the seedling stem just at or below the ground surface level causing the plant to fall over and die. In the case of cutworms and other pests, they typically travel along or within a few inches below the soil surface to eat at the plant stem and/or roots. It has been found that by creating a barrier that surrounds the plant and that extends sufficiently above the soil surface, attacks by cutworms can be prevented.
To prevent cutworm attacks, shields such as rings of plastic or paper materials have been utilized that basically comprise an annular wall that can be positioned around a newly planted seedling. For example, a ring shield can be passed over a seedling as such is planted in the ground and then pushed partially into the ground leaving a portion of the shield extending above the ground surface. A ring partially buried can provide protection from all directions. Such a ring would also provide a partial barrier for a determined degree below the soil surface based upon the depth of burying of the ring around the seedling.
Such pest barriers can be composed of a relatively permanent material, such as a plastic or metal material, or can be degradable, such as made from cardboard tubing. At the end of a growing season, the rings can be removed from the ground and thrown away or can be saved for use again. These known barriers comprise rings that are normally cut from an elongate tube of the desired material and thus provide a simple annular wall that otherwise lacks other features.
Degradable materials have also been known for making plant pots, such as comprising a biological material like compressed peat moss. By known techniques, such pots can be formed from the compressed peat moss into the shape of a container. The frailness of the material itself does not, however, lend these pots to having many features. More recently, other materials have been developed for seed planting and the transport and use of plant seedlings that are also capable of being buried into the ground with plant roots.
United States Patent Application Publication No. 2009/0272033 describes biodegradable germinating pods for seedlings. The body of the tubular pods consists of 20 to 70% cellulose, 5 to 20% calcium carbonate, 30 to 70% calcium sulfate, and micronutrients.
European Patent No. 0 716 804 discloses soil decomposing seedling pots wherein coconut shell powder is mixed into a biodegradable plastic made of carboxylic acid-based compounds such as an aliphatic acid or lactic acid. The pot is made by injection molding.